Conventionally, an angioplasty device for removing a thrombus formed in a blood vessel is known. For example, an angioplasty device disclosed in Japanese Unexamined Patent Publication No. 2000-508938 includes a catheter including an optical fiber and a laser system connected to the optical fiber. In the angioplasty device, pulsed light is output from a distal end of the optical fiber, and a thrombus is dissolved by a bubble generated by the pulsed light. In such an angioplasty device, a positional relationship between the optical fiber and a thrombus is identified by injecting a contrast medium into a blood vessel to acquire an X-ray image.